The current study examined the impact of explicit genre-based instruction on the writing ability of the graduate students in article writing skills. The participants were 60 graduate students in two groups of 30 majored in soft and hard sciences. Swales’ (1990) model was introduced to the participants in the study, applying a pre-test/post-test research design. The groups were instructed over a time period of three months followed by a post-test. To make sure of the normality of distribution of the pre- and post-test scores, a Kolmogorov Smirnov test was performed. In addition, to compare the results of pre-test and post-test, pair wised samples t-tests were run on the results of both pre-test and post-test. Results indicated that explicit instruction was effective in developing the participants in both branches of science to promote their command of developing well organized academic articles characterized with the four phase macro structure of Introduction, Method, Result, and Discussion (IMRD) which was the target genre organization in academic papers.